
for antifermion scattering.
It follows from Eq. () that the partial amplitudes \(f_{I_{3}^{\prime },I_{3}}^{\left(m\right)}\)  must satisfy the same symmetry relations as
the partial matrix elements \(S_{I_{3}^{\prime },I_{3}}^{\left( m \right)}\) ,
and we can see that the Born partial amplitudes () and
() satisfy symmetry relations (REF ), (REF ),
(REF ), and (REF ).
Eqs. () and () tell us that the leading terms of
the asymptotic forms of \(f_{I_{3}^{\prime },I_{3}}^{\left(m\right)}\)  do not
depend on \(m\) .
Furthermore, the leading terms of the elastic (\(I_{3} = I_{3}^{\prime }\) ) partial
amplitudes are \(\propto h^{2}\) , whereas those of the inelastic (\(I_{3} \ne I_{3}^{\prime }\) ) ones are \(\propto h\) .
Finally, we recall that the Born partial amplitudes and corresponding
partial elements of the \(S\) -matrix do not satisfy the unitarity condition
[1]}, [2]}.
